I'm going to go through hell for saying this.
The main focus on Spiral Knights months ago was focus on the randomized Arcade. As such, most playing should be done through this system instead of skipping levels to run through boss levels and the like.
Think about it. Mission rewards are only given to you once. What's the point of doing missions again when you have virtually no prize for doing so?
This suggestion leaves some guidelines, however.
-The Hall of Heroes can still be accessed as many times as possible.
-Boss-related missions can be played again and again, but every mission of this type will include all randomly-chosen levels associated to its current gate until the depth at which the boss levels actually begin. The Firestorm Citadel, for example, is played with all other Tier 3 depths in the mission, with determined stratum types, and areas randomly cycle.
-Tutorials and briefing missions can be played as many times as possible.
-All other Prestige missions become unplayable upon completion. To prevent abuse of simply returning to Haven after collecting money and materials from the mission and keeping everything you picked up, those collectables are lost if the mission is not completed.
I hope people take the time to read this suggestion through before they tear me limb from limb. It is only my opinion on how we fix the experience of the game for every level of player.
Me dear boy, I do agree with you wholeheartedly, but, you need to think like they do, Ask yourself," What can I do to make 3 Rings More money?"
This might offer some enlightenment.